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WARNING: kernel/rcu/tree_stall.h:1048 at rcu_check_gp_start_stall.part.0+0x1c4/0x4b0 kernel/rcu/tree_stall.h:1048, CPU#0: syz.7.4788/24562
Modules linked in:
CPU: 0 UID: 0 PID: 24562 Comm: syz.7.4788 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
RIP: 0010:rcu_check_gp_start_stall.part.0+0x1c4/0x4b0 kernel/rcu/tree_stall.h:1048
Code: 88 61 01 00 00 be 04 00 00 00 48 c7 c7 80 15 73 9b e8 c0 18 8c 00 b8 01 00 00 00 87 05 35 d2 84 19 85 c0 0f 85 3d 01 00 00 90 <0f> 0b 90 48 c7 c3 64 70 22 91 48 81 fd c0 14 bf 8e 74 5a 48 b8 00
RSP: 0018:ffffc90000007df0 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000002904 RCX: ffffffff81ee4340
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff9b731580
RBP: ffffffff8ebf14c0 R08: 0000000000000001 R09: fffffbfff36e62b0
R10: 0000000000000003 R11: 0000000000000000 R12: 1ffffffff1d01e50
R13: 0000000000000246 R14: 0000000000000002 R15: 0000000000000000
FS: 00007fbd224fb6c0(0000) GS:ffff888123de8000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c389648 CR3: 0000000058b58000 CR4: 00000000003526f0
Call Trace:
rcu_check_gp_start_stall kernel/rcu/tree_stall.h:1011 [inline]
rcu_core+0x2cb/0x10d0 kernel/rcu/tree.c:2892
handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x589/0x16c0 kernel/smp.c:892
Code: b8 00 00 00 00 00 fc ff df 48 8b 54 24 08 49 89 d5 49 89 d4 49 c1 ed 03 41 83 e4 07 49 01 c5 41 83 c4 03 e8 c9 95 0c 00 f3 90 <41> 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 2c 0f 00 00 8b 45 08 31
RSP: 0018:ffffc90006067a78 EFLAGS: 00000246
RAX: 0000000000080000 RBX: 0000000000000001 RCX: ffffc90007931000
RDX: 0000000000080000 RSI: ffffffff81fd46d7 RDI: ffff88802af18000
RBP: ffff8880b8541240 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000003
R13: ffffed10170a8249 R14: 0000000000000001 R15: ffff8880b843c880
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1057
on_each_cpu include/linux/smp.h:72 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2773 [inline]
smp_text_poke_batch_finish+0x337/0xc60 arch/x86/kernel/alternative.c:2983
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
jump_label_update+0x37a/0x550 kernel/jump_label.c:910
static_key_slow_inc_cpuslocked kernel/jump_label.c:168 [inline]
static_key_slow_inc_cpuslocked+0x82/0x120 kernel/jump_label.c:151
static_key_slow_inc+0x1a/0x30 kernel/jump_label.c:191
kvm_create_vm virt/kvm/kvm_main.c:1204 [inline]
kvm_dev_ioctl_create_vm virt/kvm/kvm_main.c:5493 [inline]
kvm_dev_ioctl+0x104a/0x1a50 virt/kvm/kvm_main.c:5535
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbd2159de59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fbd224fb028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fbd21826090 RCX: 00007fbd2159de59
RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000009
RBP: 00007fbd21633e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbd21826128 R14: 00007fbd21826090 R15: 00007ffdb8a7f3a8
----------------
Code disassembly (best guess):
0: b8 00 00 00 00 mov $0x0,%eax
5: 00 fc add %bh,%ah
7: ff lcall (bad)
8: df 48 8b fisttps -0x75(%rax)
b: 54 push %rsp
c: 24 08 and $0x8,%al
e: 49 89 d5 mov %rdx,%r13
11: 49 89 d4 mov %rdx,%r12
14: 49 c1 ed 03 shr $0x3,%r13
18: 41 83 e4 07 and $0x7,%r12d
1c: 49 01 c5 add %rax,%r13
1f: 41 83 c4 03 add $0x3,%r12d
23: e8 c9 95 0c 00 call 0xc95f1
28: f3 90 pause
* 2a: 41 0f b6 45 00 movzbl 0x0(%r13),%eax <-- trapping instruction
2f: 41 38 c4 cmp %al,%r12b
32: 7c 08 jl 0x3c
34: 84 c0 test %al,%al
36: 0f 85 2c 0f 00 00 jne 0xf68
3c: 8b 45 08 mov 0x8(%rbp),%eax
3f: 31 .byte 0x31